Carton adapted for field assembly

ABSTRACT

Carton which can be completed at situs of packing without tools or assisting materials formed from a flat prescored paperboard blank, with attached rigid panels to provide the ends of the carton, the end panels incorporating hook members engaged by the edges of cutouts in the blank located adjacent the marginal edge portions of the blank when these portions are folded in along score lines, whereby the hook members interlock with the edges of the cutouts to form first an open carton, and secondly a fastened-down lid.

United States Patent Inventors Halmar J. Webb 4263 Forman Ave., North Hollywood, Calif. 91602; Walter E. McKinley, 2125 Caddington, San Pedro, Calif. 90732 Appl. No. 888,800

Filed Dec. 29, 1969 Patented Jan. 4, 1972 CARTON ADAPTED FOR FIELD ASSEMBLY 11 Claims, 8 Drawing Figs.

US. Cl 229/23 Int. Cl. 865d 11/20 View of Search 229/23 B,

[56] References Cited UNITED STATES PATENTS 3,417,909 12/1968 Stern 206/52 3,487,991 1/1970 Stem.... 229/23 B 3,373,921 3/1968 Crane 229/23 B Primary Examiner.lames B. Marbert Attorney-Huebner & Worrel ABSTRACT: Carton which can be completed at situs of packing without tools or assisting materials formed from a flat prescored paperboard blank, with attached rigid panels to provide the ends of the carton, the end panels incorporating hook members engaged by the edges of cutouts in the blank located adjacent the marginal edge portions of the blank when these portions are folded in along score lines, whereby the hook members interlock with the edges of the cutouts to form first an open carton, and secondly a fastened-down lid.

CARTON ADAPTED FOR FIELD ASSEMBLY BACKGROUND OF THE INVENTION Wooden lugs or cartons used for gathering, also field packing, of fruits and vegetables, and packing-house packing of frozen meats and other foods, are becoming increasingly expensive, must be factory finished except for lidding, the lugs or cartons occupy excessive space during distribution and require a mechanical lidding operation after filling. Corrugated boxes or cartons now in use for such purposes present the same problems in distribution and lidding, the lidding usually being done by stapling or application of adhesive.

The cartons used by movers which 27a delivered collapsed, may be opened at the site of use, and the four extending flaps at an end intertucked in a well-known manner. These do not provide the stability required for the packing of commodities such as designated above. These cartons are especially fragile if the horizontal area is large relative to the height, as is desired in cartons for packing fruits, vegetables, etc. Pasteboard suit and clothing boxes cannot meet the requirements, and would not be adaptable to the intended use. One reason for the latter is that if the board were sufficiently heavy and strong it would not be feasible to work tongues through slits for locking sections together. Moreover, if so fabricated they will be ungainly.

There has been a serious need, unfilled until the present invention, so far as applicants are aware, for a field lug or carton, which could be stored and distributed in flat incomplete condition, completed at the site of use without tools or assisting materials, closed after filling, and possess the rigidity needed for protection of the contents, and stacking of filled and closed cartons.

SUMMARY OF THE INVENTION The present invention has as its primary object, the provision of a carton of the character needed, and the knock-down, flat parts which are required for assembly. These parts can be folded and interlocked by hand, without tools, to first form an open box. After filling, the closing can be done in a similar manner.

Essentially, we provide a generally rectangular blank made of material such as corrugated board. Centrally attached at each side of the blank is a panel of rigid material which will be bent up to provide an endv wall. Hook members are incorporated in marginal regions of the end wall members.

Sections of the blank defined by score lines will be bent in the position of sidewalls of the carton, and tabs containing cutouts will be turned in so that the hooks engage in the cutouts.

These steps form an open carton. When filled, the canon is lidded by folding over sections toward each other, and bending tabs down for the edges of cutouts therein to be engaged with hooks in the upper edge region of the end walls.

Further details and advantages, will be apparent from subsequent description.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of the carton in complete closed condition; contents are omitted, to show portions of the interi- FIG. 2 is an end view of the carton with parts broken away;

FIG. 3 is a vertical section taken on the line 3-3 of FIG. 2;

FIG. 4 is a fragmentary horizontal section taken on the line 44 of FIG. 2;

FIG. 5 is a fragmentary vertical section taken on the line 5- 5 of FIG. 2;

FIG. 6 is a fragmentary horizontal section taken on the line 6-6 of FIG. 2;

FIG. 7 is a top plan view of the blank with appended end panels used in forming the carton; and

FIG. 8 is a fragmentary section taken on the line 8-8 of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT The carton when completed comprises a flat bottom 10, sides 11, ends 12 and a top I3.

To understand its structure and method of assembling it, reference should be had to FIGS. 7 and 8. A flat blank 15, preferably formed of corrugated paperboard, is generally rectangular in shape and includes a number of features. A bottom panel 20 is defined by score lines 21, 22, 23 and 24.

This panel is rectangular and ordinarily will be slightly elongated as determined by the spacing of the score lines 21 and 23 in contrast to the lesser spacing of score lines 22 and 24. The panel may include ventilating apertures 25.

Extending from the score line 22 is a side panel 26, bounded at one edge by the score line 22 and at its opposite edge by a score line 27. Extending from this side panel is one section 28 of a top panel bounded on one edge by the score line 27 and terminating in an end edge 29.

An identical extension of side panel and a section of a top panel projects from the score line 24 outwardly and the parts are designated by the same reference numerals accompanied by the letter a.

Intersecting the score lines 27 and 27a are rectangular cutouts 30 and 30a which serve two functions in the completed carton. They provide additional ventilation ports, and also handgrips, as may be clearly seen in FIG. 1.

The score line 21 of the bottom panel is projected in both directions through the side panels and top panels; the same thing is true of score line 23.

Extending transversely outwardly from the score line 21 and its projections are tabs 35, 36, 37, 38 and 39. Similar tabs 35a, 36a, 37a, 38a and 39a extend outwardly from the score line 23 and its projections. The outer edges of these tabs on each side of the blank are in straight alignment, which, in conjunction with the edges 29 and 29a, impart the general rectangular configuration to the corrugated blank.

Of course, this blank is flat and can be die cut from a single sheet of corrugated board in one operation.

The tabs could be formed by merely extending the transverse score lines 27, 22, 24 and 27a with a complete cutthrough outwardly from the score lines 21 and 23. It is preferable however, to form these tabs by V-notches 42 which provide convenient clearance in folding operations subsequently described.

Appended to the corrugated board blank 15 are opposite end plates 45 and 46. They are identical. They should be of generally rigid construction, preferably being molded of a suitable plastic. They are each rectangular in plan and are defined by what may be designated a bottom edge 50, a top edge 51 and end edges 52 and 53. Each is shown with a total thickness substantially greater than the thickness of the corrugated board for several purposes. First, it is necessary that the thickness at the top, bottom and end edges be sufficient to form slots or channels 55 and 56 for the reception of tabs of the corrugated blank; second for rigidity and yet for lightness of construction we form these end plates with a central depression 57'which results in a relatively thin center wall section 58 but reinforced by the enclosing channel structure which in vertical elevation has the appearance of a rectangular frame as shown in FIG. 1. The flat surface of the wall section 58 on the inside of the carton, uppermost in FIG. 7, extends over the entire area of the plate.

The channels 55 and 56 are shown as formed with a plurality of parallel ramps 60 with inclined forces 61 merging into horizontal surfaces 62 which narrows the channel but snugly receive the blank tabs. As illustrated, tab 37a is secured in the channel 56 by staples 65. Securement optionally could be, however, by the same provisions subsequently described in connection with securement with other tabs inserted in channels of the end panels. The channel 56 is disposed only in the bottom edge. The channel 55 is located in the top and end edges.

Preferably, the corrugated blank is delivered with the end panels attached so that the overall carton material, ready for assembly, may be stacked and delivered flat. The assembly may be completed in the field or the packing house or anywhere else by simple manipulations and without the use of any tools. This is made possible by structural features to be further described.

The carton blank is provided with a plurality of cutouts 68, all of which are given the same reference numeral because they all function in a similar manner with respect to the hooks formed in the channels of the end panels. The cutouts 68 on one side of the blank are aligned along one edge with the score line 21 and the cutouts 68 on the opposite side are all aligned with the score line 23. Each of these cutouts provides an edge 69 which cooperates for interlocking with a tooth-shaped hook member in the channel 55 to be described.

Such hook members are all designated 72 and they are formed with inclined surfaces 73 and abutment or stop surfaces 74. The relationship of hook members and cutout edges is somewhat analogous to a pawl and ratchet arrangement.

The channels 55 and 56 in the end panels in toto run around all four edges of each end panel and the hook members 73 are disposed in three of the sides comprising the channel 55', the abutment surfaces 74 are disposed inwardly of the channel. These hook members are positioned for registration with respective cutouts 68 when the blank and the end panels are folded along score lines and the tabs are folded into juxtaposition.

The carton is assembled from the blank and end panels of FIG. 7 in the following manner. The end panels 45 and 46 are folded up along score lines 21 and 23 so that they are approximately at 90 to the plane of the bottom panel 20. Thereupon, the side panels 26 and 26a are folded up along the score lines 22 and 24. These manipulations provide the general form of a rectangular box open at the top. The next step is to fold the tabs 36 and 38 inwardly along the projection of the score line 21, sliding each of these tabs into a channel. The tabs will ride over the inclined face 73 of the teeth and when sufficiently inserted will snap into place with an edge 69 in tight engagement with the abutment face 74 of the teeth. This connection is given impetus by interposition of the ramps 60. Similar steps are employed for the tabs 36a and 3811.

When both side panels are thus secured to the end panels, a firm open boxlike structure is completed.

After filling, it remains for the top panels 28 and 28a to be folded down on the score lines 27 and 27a. Thereupon the tabs 35, 35a, 39 and 390 are folded down along the projection of the score lines 21 and 23 and forced into the upper channels of the end panels until the cutouts slip over the hooks in such channels. This completes the carton and it is ready for handling and shipment. The sturdiness of the end panels is sufficient for the carton to be stacked; however, optionally we may employ wooden lath or other reinforcing strips 75 which may be stapled as at 76 or otherwise secured to the top panel sections. If these reinforcements are used, they would be attached during the fabrication of the blank and end panels. Such reinforcements have some utility not only for bracing purposes if the carton should become misaligned in, stacking, but they also afford added rigidity to the top of the completed carton due to proximity in the handgrips as shown.

The top is illustrated as providing a central opening. Obviously a complete cover can be achieved by making the top panels wide enough to meet at the center; or a single panel could be designed to substitute for the two panels illustrated.

Although we have herein shown and described our invention in what we have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of our invention.

We claim:

1. A prefabricated carton which can be assembled by hand without tools or adhesive from a generally flat subassembly and comprising a stiff paperboard generally rectangular bottom and sides, with marginal tabs extending from at least the sides and formed of integral sheet structure, generally rigid rectangular ends embodying a peripheral channel, the tabs extending into respectively adjacent portions of the channel, tab engagement means comprising hook members in at least the side portions of the channel, at least the side tabs embodying means comprising cutouts with edges which abut against the hook members interlocking thereby with the tab engagement means.

2. A prefabricated carton as defined in claim 1 in which at least the channel at the sides embodies tooth-type hook members with inner abutment faces and outer tapered surfaces, and guide ramps with surfaces tapered oppositely with respect to the tapered surfaces of the hook members disposed on a wall of said channel opposite said hook members; whereby the tabs are forced between the respective tapered surfaces so as to bring an edge of each cutout into engagement with the inner abutment face of a hook member.

3. A prefabricated carton as defined in claim 2 in which each end comprises a wall which is plane flat on the inside, and of a predetermined thickness in the central region, and the channel is formed by a framelike marginal extension on the outside of the wall surrounding the central region.

4. A prefabricated carton as defined in claim 1 in which said carton comprises a stiff paperboard generally rectangular bottom, sides and top with marginal tabs extending from at least the sides and top, in which the tab engagement means comprises hook members in at least the side and top portions of the channel, and in which at least the side and top tabs embody means comprising cutouts with edges which abut against the hook members interlocking thereby with the tab engagement means.

5. A prefabricated carton as defined in claim 1 in which said generally rigid rectangular ends embody a peripheral channel having sidewalls parallel with the general plane of the end wall and an opening around the edge thereof, and in which said tabs extending into said channel are disposed normal to the planes of the respective portions of the carton from which they extend.

6. A generally flat subassembly from which a carton can be field assembled by hand without tools or adhesive, comprising: a stiff paperboard generally rectangular blank, longitudinal score lines in the blank spaced apart and parallel and defining the ends of the carton, transverse score lines in the blank intersecting the longitudinal score lines and dividing the blank intersecting the intermediately disposed bottom panel and op posite side panels, tabs extending outwardly from the longitudinal score lines adjacent the bottom panel and the side panels, hook engaging means in at least the tabs adjacent the side panels, generally rigid rectangular end members attached to the tabs of the bottom panel and embodying a peripheral channel, hook elements disposed in said channel at least in such locations as to be engageable by said hook engaging means when said blank is formed in carton shape, whereby a carton may be assembled by forming the end members and the side panels into the general shape of an open rectangular box, bending in the tabs along their respective score lines and interlocking the hook engaging means of the tabs with the hook elements of the end members thereby interlocking the sides and ends.

7. A generally flat subassembly from which a carton can be field assembly by hand without tools or adhesive, as defined in claim 6 additionally provided with a longitudinal score line defining at least one top panel, a tab extending outwardly from said score line, hook engaging means in said tab and hook elements disposed in said channel in such location as to be engageable by said hook engaging means when said blank is formed into carton shape.

8. A generally flat subassembly from which a carton can be field assembled by hand without tools or adhesive, as defined in claim 6 in which said generally rigid rectangular end members embody a peripheral channel having sidewalls parallel with the general plane of the end member and an opening around the edge thereof, and in which said tabs are arranged disposed within the channels.

11. A subassembly as defined in claim 10 in which the hook elements are in the fomi of teeth each with an entrance incline and an inner abutment face, and entrance ramps are disposed in the channel opposite the teeth, the ramps having surfaces inclined opposite the incline of the teeth. 

1. A prefabricated carton which can be assembled by hand without tools or adhesive from a generally flat subassembly and comprising a stiff paperboard generally rectangular bottom and sides, with marginal tabs extending from at least the sides, and formed of integral sheet structure, generally rigid rectangular ends embodying a peripheral channel, the tabs extending into respectively adjacent portions of the channel, tab engagement means comprising hook members in at least the side portions of the channel, at least the side tabs embodying means comprising cutouts with edges which abut against the hook members interlocking thereby with the tab engagement means.
 2. A prefabricated carton as defined in claim 1 in which at least the channel at the sides embodies tooth-type hook members with inner abutment faces and outer tapered surfaces, and guide ramps with surfaces tapered oppositely with respect to the tapered surfaces of the hook members disposed on a wall of said channel opposite said hook members; whereby the tabs are forced between the respective tapered surfaces so as to bring an edge of each cutout into engagement with the inner abutment face of a hook member.
 3. A prefabricated carton as defined in claim 2 in which each end comprises a wall which is plane flat on the inside, and of a predetermined thickness in the central region, and the channel is formed by a framelike marginal extension on the outside of the wall surrounding the central region.
 4. A prefabricated carton as defined in claim 1 in which said carton comprises a stiff paperboard generally rectangular bottom, sides and top with marginal tabs extending from at least the sides and top, in which the tab engagement means comprises hook members in at least the side and top portions of the channel, and in which at least the side and top tabs embody means comprising cutouts with edges which abut against the hook members interlocking thereby with the tab engagement means.
 5. A prefabricated carton as defined in claim 1 in which said generally rigid rectangular ends embody a peripheral channel having sidewalls parallel with the general plane of the end wall and an opening around the edge thereof, and in which said tabs extending into said channel are disposed normal to the planes of the respective portions of the carton from which they extend.
 6. A generally flat subassembly from which a carton can be field assembled by hand without tools or adhesive, comprising: a stiff paperboard generally rectangular blank, longitudinal score lines in the blank spaced apart and parallel and defining the ends of the carton, transverse score lines in the blank intersecting the longitudinal score lines and dividing the blank into an intermediately disposed bottom panel and opposite side panels, tabs extending outwardly from the longitudinal score lines adjacent the bottom panel and the side panels, hook engaging means in at least the tabs adjacent the side panels, generally rigid rectangular end members attached to the tabs of the bottom panel and embodying a peripheral channel, hook elements disposed in said channel at least in such locations as to be engageable by said hook engaging means when said blank is formed into carTon shape, whereby a carton may be assembled by forming the end members and the side panels into the general shape of an open rectangular box, bending in the tabs along their respective score lines and interlocking the hook engaging means of the tabs with the hook elements of the end members thereby interlocking the sides and ends.
 7. A generally flat subassembly from which a carton can be field assembled by hand without tools or adhesive, as defined in claim 6 additionally provided with a longitudinal score line defining at least one top panel, a tab extending outwardly from said score line, hook engaging means in said tab and hook elements disposed in said channel in such location as to be engageable by said hook engaging means when said blank is formed into carton shape.
 8. A generally flat subassembly from which a carton can be field assembled by hand without tools or adhesive, as defined in claim 6 in which said generally rigid rectangular end members embody a peripheral channel having sidewalls parallel with the general plane of the end member and an opening around the edge thereof, and in which said tabs are arranged so as to be disposable normal to the planes of the respective portions of the blank from which they extend for insertion into said channel.
 9. A subassembly as defined in claim 6 in which the hook engaging means in the tabs comprise notches in the tabs.
 10. A subassembly as defined in claim 9 in which the end members are molded plastic, embody peripheral channels for receiving the tabs of the blank, and the hook elements are disposed within the channels.
 11. A subassembly as defined in claim 10 in which the hook elements are in the form of teeth each with an entrance incline and an inner abutment face, and entrance ramps are disposed in the channel opposite the teeth, the ramps having surfaces inclined opposite the incline of the teeth. 